Coating reactors are being used for the coating of substrates, having a bottom part, a top part and side walls, a supply line for gaseous media into the interior of the coating reactor and microwave windows for coupling in high-frequency energy or microwave energy by means of which a plasma is ignited in the interior of the reactor. The microwave energy is preferably pulsed microwave energy. A device and a method for coating a substrate by means of pulsed microwave energy is disclosed in DE 38 30 249 C2, for example.
DE 44 14 0831 A1 describes a device for producing thin films on plastic substrates by means of gas phase deposition via low pressure plasma with two diametrically opposed sources and a coating chamber in which the substrates are held between the range of action of both sources.
U.S. Pat. No. 6,010,755 describes a coating apparatus for applying protective layers on a magnetic memory device, where an ECR plasma is generated in a vacuum chamber and where the ECR plasma is coupled in from opposite sides.
All of the devices according to prior art are disadvantageous in that inhomogeneous coatings are deposited, especially in the edge areas, the coating conditions vary from one substrate to be coated to the next and therefore they are difficult to reproduce, and the volume of such reactors is relatively large, so that the gas exchange times, and thus the process times are relatively long. Another disadvantage of the devices according to prior art is that variations in the coating thickness cannot be prevented.
Therefore, the aim of the invention is to provide a device for coating substrates with which the above mentioned disadvantages are prevented.